Full charge capacity amount on the MBP battery?

This is not a problem. 5500MAH is just an average or baseline. A new batteries charge capacity will range from 5300-5700MAH. Mine brand new was 5398MAH. As long as it is above 4400MAH, it is within apples spec.

But I am wondering whether after each recharge the battery's 'reported' capacity reduces a small amount which, over time, can result in a significant drop in capacity? Can this lost capacity be recovered by re-calibrating or is the reduced capacity simply a fact of life that will lead to the battery's eventual replacement? REGARDS Phil

Hi phillharve,

The Full Charge Capacity will always be oscillating between 80 % to 100 % of its value. This is affected by factors such as ambient temperature , battery built quality and style of usage.

It is quite random,battery calibration is only done when the Full Charge Capacity drops below 80 % of its optimal value and the charge cycle is still far less than 300.

Dont get too worried over the battery health,it will be good as long it stays above 80 or 90 % of the Full Charge Capacity.

Hello
Can you please tell me how you checked what is the charge capacity on the MBP battery ? Ihad a battery replaced under the '07 replacement program and now find that I get maybe 30 minutes battery life, doing simple things like sending / checking email (hotmail) or writing a document (neooffice). Pretty poor performance but I am not sure how to check what I should have (ie: 80%-90% of Full Charge Capacity) being unable to look up my FCC. Appreciate anyone's help. Thanks.Russell (russel_ferrier@mac.com)

The most convenient way is to download iStat Pro widget

or

Go to About This Mac>More info

In System Profiler, go to Power.(Maximum charge is between 5450 to 5700 mAh)

Thanks BadPenn

The 'oscillating' reading is the important thing. I was beginning to think that each recharge lost a few mAH capacity from the battery - permantly. This is my second battery, the first being replaced under warranty after 2 years for displaying 'intermittent shutdown' problems. The replacement runs cooler whilst charging but I was beginning to think Apple had sacrificed battery life for better performance. REGARDS Phil

Yup,I couldn't agree more with your opinion.Battery technology has not be able to keep on par with the development of CPU technology and that is why we have catagories such as ultraportables on the market.

Even Apple has its own answer to it ---- Macbook Air.

This is also my 2nd battery,my first battery's full charge capacity dropped to a horrendous 2% after a night while the charge cycle is 67.

Try to avoid infrequent usage and inconsistent recharging, or even consider changing the environment where you usually place your laptop..see whether it helps.

Thanks BaddPenn

I think therefore if what the general comments here are correct, that my 15" MBP battery should have a full charge capacity of around 5550mAh, therefore I have a problem if my f.c.c. is only :

Full Charge Capacity (mAh): 973
Remaining Capacity (mAh): 928
Amperage (mA): 0
Voltage (mV): 12419
Cycle Count: 235

This is my second battery, the first being replaced under the faulty / replacement program in 07. Any suggestions...another new battery needed ?

Regards
Russell (russell_ferrier@mac.com)

Hi jeruden

The battery readings you quote are seriously abnormal and far below what the ought to be. The 5550mAh seems reasonable if that is what Apple quote should be your battery capacity. With readings like yours I wouldn't expect you Mac' to run on battery power for very long, probably well under an hour. If true, you either have a serious battery problem or your charging circuit isn't working correctly. It also occurred to me that maybe the software that reports your battery's condition may be defective. REGARDS Phil.

Hi - I would like to add that I used 'iStat Pro', 'SlimbatteryMonitor' and 'Battery Health Monitor'. I used to use the 'Coconut Monitor' and 'iBatt2' applications but they don't appear to work under 10.5.2. The readings I get from the 3 applications that work are consistent. REGARDS Phil

Hi - My replacement MBP battery is now on a Cycle Count of 12 and the first thing that is immediately apparent is how much cooler the new battery runs compared with the original battery. I am now even more certain that the original battery had an internal fault or a design flaw that caused it to overheat when charging. However, I am surprised that it managed to last 2 years before exhibiting the widely reported 'premature shutdown symptom'. As reported previously, the original battery did not deform or start to come apart and as a consequence my MBP has sustained no damage whatsoever. However, I would recommend any MBP owner with a suspect battery to periodically remove and examine the battery for signs of distortion.

I will be closely monitoring the performance of the new battery, particularly the variation in its Full Charge Capacity versus Cycle Count versus Voltage in order to ascertain its typical life span. This is an expensive battery and I need to extend its life for as long as possible. I expect to get more than the 2 years of the original battery. REGARDS Phil

Thanks Phil for all the replies. I think therefore it's time for a trip (ho hum) back to the apple store here in Buenos Aires to see if they'll replace yet another battery ! This one runs for maybe 20 minutes so I have to live plugged in. Wish me luck. Regards, Russell

Hi jeruden - I am surprised to learn that you have to replace your battery again. Is this a record? I do wish you luck with your latest claim. I was very nervous running on external power for a week and no battery. I had to ensure I did not snag the power cable and pull it off the Magsafe connector. This is something I do frequently so I had to be extra, extra careful.

I seem to have been more fortunate with my replacement battery. It runs as cool as my Dell Precision M65 battery. However, battery life is little improved over the original when it was working correctly. I might get 3+ hours if I reduce display brightness and invoke other power-saving features. Maybe its capacity will improve with use. However, I have noticed that the new battery charges much faster than the original AND it stays cooler. REGARDS Phil.

UPDATE - I have found that by reducing the intensity of the display, even by a quarter, will add more than a hour to the life of the battery following a full charge. Reducing the intensity to just one quarter will give a battery life of between 4 and 4.5 hours. Putting the drive to sleep when not required extends the life to over 5 hours.

These figures are slightly better than the battery that was replaced under warranty. This suggests that their capacities are similar. I originally thought the old battery had a shorted cell, or cells, causing the battery to overheat and have a reduced capacity. I now believe I was wrong.

The Cycle Count of the new battery has reached 20 and the Full Charge Capacity 'appears' to be gradually reducing with each charge. This seems incorrect to me and I am now wondering if some kind of performance compromise has been implemented to reduce the frequency of battery failures.

I would be interested in hearing from any other forum members who has noticed anything different about the performance of the newer batteries?

I previously reported that the new battery runs cooler than the original. I have been monitoring its temperature during charging and not charging and its temperature is still gradually dropping and I am no longer suffering the 'hot lap' syndrome which I assume was because the original battery was faulty.

I imagine that the new battery requires a settling-in period so maybe the temperature will eventually stabilize. Is the charging cycle controlled by a process that can be updated? REGARDS Phil.

UPDATE - I am attempting to re-calibrate my replacement battery because I have noticed that after each recharge the battery capacity reduces slightly. If this continues the battery capacity will fall below the minimum required level to operate the MBP. This point will be reached well within the 300 Cycle Count which I assume is the lifespan of the battery. I have already reached a Cycle Count of 30 after just a few weeks. At this rate the battery will last just barely 1 year. The original faulty battery managed a Cycle Count of 230 and a life of 2 years before replacement. How important is it to rest the exhausted battery before recharging? Apple recommends at least 5 hours, presumably time enough for the battery to cool down. REGARDS Phil